In a digital communication system, an audio signal is encoded into bit streams to be transmitted to a receiving end through a channel. An Adaptive Multi-Rate (AMR) vocoder, which is widely used in a digital communication system, calculates necessary parameters from a signal that is modeled by an auto-regressive process, and then converts the calculated parameters into bit streams to transmit the bit streams. Such bit streams are gathered to form one audio frame, and if a channel state deteriorates during frame transmission, an error may occur.
In general, if an error occurs, parameters of an audio signal that exist in the frame are replaced by errorless parameters extracted from the previous frame. This is to minimize deterioration of the sound quality through concealment of the audio signal parameters in the frame where the error exists, and there is a need for a method capable of heightening a reception performance of the audio signal through removal or weakening of components of a specific band or a desired band in consideration of person's perception.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.